[olivero]

I would be looking at what's driving the motor at this point, it's a single phase power supply from the wall, the motor is using 3 phase, 50 hz as it's a german motor.

The Convotherm 4 uses VFD's, I don;t think this unit uses a VFD but it uses a transformer if it's anything like the OGS model.

Voltage into the unit and the 3 wires supplying power is where I would be looking.

Obviously the motor is not the problem if it was just replaced, so it's either bad wires or bad voltage at thos point.

[olivero]

Patrick, did you replace Scott? He told me he was going to be doing something else, but I wasn't sure who the new administrator/mayor is?

The problem I have when I try to reply is I have to refresh the page before I can reply, I click on the link and enter the post, but then have to refresh before the reply button works.

[olivero]

Seems like this might have done it, haven't heard of a problem for the last 3 days, which so far is the longest by far since starting the repair.

Thanks for the assistance, if the problem isn't fixed, i'll be back 🙂

[olivero]

Do you have a picture?

IF it's a mteal sleeve, generally, knock'er loose and some torching will help, plastic can sometimes be easier to just break off if it's being replaced.

[olivero]

@ectofix No, reading from hot leg to neutral.

I looked into this more, I gave it some thought, stared at it, hit it with something and had an idea.

When I opened the motor back up to look for myself (someone else changed the switch inside) I started messing with the actuator part itself, I noticed it moved on the shaft which seemed a bit off, there's about 1-2″ of space where the actuator can move back and forth, which in theory could make it loose contact with the switch.

I checked the actuactor and it had a crack down the center where it sits on the shaft, so I figured it could be. To me, since the low to high made a difference and it seems to have to be hot before the problem really appears, I figured it could make sense that it was just moving enough to partially open that safety by sliding away from the switch.

I 3D printed a spacer to put on the shaft that sits between the top of the actuator and the snap ring which will prevent it from sliding around. So far it's not making noises like it was before, but the true test will be tomorrow when it's on for most of the day.

I'm 100% sure I'm measuring the switch in the right place, I can't buy the motor and I definetley can't buy the actuator. I'd have to buy the “new and improved” version which is a new motor and blower wheel.

The mechanism itself works every time, I set it up in my shop so I could ohm the switch when it runs and see the actuation when it happens, it's gotta be either the switch itself or that actuator.

Prior to making the spacer, I put it back together to see if it was moving and when it's actuated, the top of the actuator was riding on the switch, which I believe is wrong, after putting in the spacer, there was a 1-2MM gap, so it seems to have made a difference.

Time will tell.

I've been throwing parts at this thing but so far nothing has worked, I really didn't think it would be so complicated.

[olivero]

Might be a stupid question but Is there power on the coil on the contactor?

It could be the coil is fried, it's happened before on some of my equipment.

[olivero]

Sounds awesome.

[olivero]

Yup, either a TXV, fully clogged drier or low charge.

Generally they'll run into a vacuum if they are low, or restricted either by dryer or faulty TXV.

If I'm in doubt, I just add some refrigerant and watch the low side, if the low side stays low but the head goes up then it's not a leak, but a restriction. If the high side stays or only goes up slightly and the low side comes up, then it's a leak most likely.

Usually does the trick.

BUT if it IS a leak, and it IS 0 (or vacuum) then you probably have a moisture and non condensables in the system at which point, you might add refrigerant and the numbers get all wonky, so you could just try to pull whatever is left of the charge and weigh in new refrigerant and then see what happens, if the low side drops out immediately and high side shoots up, it's restricted

[olivero]

I think the idea of checking in series is the best way to start, I've never thought of doing that when getting nuisance trips, but seems like it would help you figure out where to look.

Otherwise I had a hot box (kind of not related but kind of related) which had a nuisance trip every couple of days or every week or whatever, it was random and it would trip the GFCI, turned out to be one of the convection fans was leaking to ground, didn't find it before because I would reset it, and it would be fine, figured it was moisture or something odd, started sealing up all kinds of places but it would still happen.

Then eventually it wouldn't reset and I narrowed it down to that motor, replaced it and it hasn't been a problem since.

Sometimes it can be odd things, that's why I think narrowing it down is well worth it's time before you start throwing parts at it.

[olivero]

Yeah, it's odd, it seems to be functioning as it should, it was just easy to move around.

I think the counterbalance was in place, I didn't specifically check but nothing seemed to be missing when I inspected the rest of the piece.